Re: Ariane 5 failure

[shmuel@os2bbs.com]

In <3266741B.4DAA@ansoft.com>, Ravi Sundaram <ravi@ansoft.com> writes:
>Ralf Tilch wrote:
>> The reason that the software wasn't checked:
>> It was too 'expensive'?!?!.
>
>	Yeah, isn't hindsight a wonderful thing?  
>	They, whoever were in charge of these decisions,
>	too knew testing is important.  But it is impossible
>	to test every subcomponant under every possible
>	condition. There is simply not enough money or time
>	available to do that.

Why do you assume that it was hindsight? They violated fundamental
software engineering principles, and anyone who has been in this business
for long should have expected chickens coming home to roost, even if they
couldn't predict what would go wrong first.

>	Richard Feyman was examining the practices of NASA and
>	found that the workers who assembled some large bulkheads
>	had to count bolts from two refrence points. He thought
>	providing four reference points would simplify the job.
>	NASA rejected the proposal because it would involve 
>	too many changes to the documentation, procedures and
>	testing. (Surely You are joking, Mr Feyman I? or II?)
>
>	So praise them for conducting a no nonsense investigation
>	and owning up to the mistakes.  Learn to live with
>	failed space shots. They will become as reliable as
>	air travel once we have launched about 10 million rockets.

I hope that you're talking about Ariane and not NASA Challenger; Feynman's
account of the behavior of most of the Rogers Commission, in "Why Do
You Care ..." sounds more like a failed coverup than like "owning up to 
their mistakes", and Feynman had to threaten to air a dissenting opinion
on television before they agreed to publish it in their report.

	Shmuel (Seymour J.) Metz
	Atid/2